         (-> (f/parallelize c [1 2 3 4 5])
             (f/map (f/fn [x] (* 2 x)))
             f/collect
-            vec) => [2 4 6 8 10])
+            #_vec) => [2 4 6 8 10])
 
       (fact
         "map-to-pair returns an RDD of (K, V) pairs formed by passing each element of the source

                              ["key2" 4]
                              ["key3" 5]])
            (f/count-by-key)) => {"key1" 2, "key2" 2, "key3" 1})
      )))

                        ["key1" [[2] [22]]]
                        ["key2" [[3] nil]]])

      (fact
        "sample returns a fraction of the RDD, with/without replacement,
        using a given random number generator seed"
        (-> (f/parallelize c [1 2 3 4 5 6 7 8 9 10 11 12 13 14 15])
            (f/sample false 0.4 10)
            f/collect) => [1 4 7 11 14])

      (fact
        "fold"
        (-> (f/parallelize c [1 2 3 4 5])
            (f/fold 0 (f/fn [x y] (+ x y)))) => 15)

      #_(fact
        "group-by"
        (-> (f/parallelize c [["key1" 1]
                              ["key1" 2]
                              ["key2" 3]
                              ["key2" 4]
                              ["key3" 5]])
            (f/group-by (f/fn [x] (first x)))
            (f/map f/untuple)
            f/collect
            vec) => [["key1" [1 2]] ["key2" [3 4]] ["key3" [5]]])

      #_(fact
        "group-by-key"
        (-> (f/parallelize c [["key1" 1]
                              ["key1" 2]
                              ["key2" 3]
                              ["key2" 4]
                              ["key3" 5]])
            f/group-by-key
            (f/map f/double-untuple)
            f/collect
            vec) => [])

      #_(fact
        "flat-map-to-pair"
        (-> (f/parallelize c [["Four score and seven years ago our fathers"]
                              ["brought forth on this continent a new nation"]])
            (f/flat-map-to-pair (f/fn [x] (map (fn [y] [y 1])
                                               (clojure.string/split (first x) #" "))))
            #_f/untuple
            #_f/collect
            #_vec) => [["Four" 1] ["score" 1] ["and" 1] ["seven" 1] ["years" 1] ["ago" 1]])
      )))

(facts
